Mobile unit having internet protocol functionality

ABSTRACT

A mobile unit includes a handset and a removable storage module having a unique storage module identity, for storing information specific to a user, including an Internet Protocol (IP) address. Additional information regarding a Public Land Mobile Network (PLMN) and International Mobile Subscriber Identity (IMSI) which uniquely identifies the subscriber is also stored in the removable storage module. Upon successfully camping on a cell of a mobile network, the IP address is forwarded to an IP-based network capable of communicating with the mobile unit. In an alternate embodiment, the mobile unit has multi-network capabilities which allow it to communicate with an IP-based network and a cellular network at the same time. In another embodiment, existing cellular network services for the mobile unit having multi-network capabilities are routed through the IP-based network.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.10/441,432, filed on May 20, 2003, which issued as U.S. Pat. No.7,640,038 on Dec. 29, 2009, which claims priority from U.S. ProvisionalApplication No. 60/382,361, filed on May 22, 2002, which is incorporatedby reference as if fully set forth herein.

FIELD OF THE INVENTION

The present invention is related to the identification of users ofwireless equipment. More specifically, such wireless equipment may beidentified using an Internet Protocol (IP) address stored therein toaccess an IP-based network.

BACKGROUND

In GSM (Global System for Mobile communications) systems, a mobilestation (MS) consists of a wireless terminal (i.e., handset) and aremovable smart card called a Subscriber Identity Module (SIM). In 3rdGeneration (3G) Universal Mobile Telecommunication Systems (UMTSs), UserEquipment (UE) consists of mobile equipment (ME) and a removable smartcard called the UMTS Subscriber Identity Module (USIM). The MEcommunicates with a UMTS Terrestrial Radio Access Network (UTRAN) node,which in turn, may establish a connection to a Circuit Switched (CS) orPacket Switched (PS) Core network.

An International Mobile Equipment Identity (IMEI) uniquely identifiesthe mobile equipment. The SIM or USIM card contains an InternationalMobile Subscriber Identity (IMSI) which uniquely identifies thesubscriber. The IMEI and the IMSI are independent, thereby allowingpersonal mobility.

In the case of 3G UMTSs, a base station controller corresponds to aradio network controller (RNC). There, a plurality of base stations arecontrolled by a node B, which in turn has a connection to the RNC.

The SIM or the USIM provides personal mobility so that a user can haveaccess to subscribed services irrespective of a specific terminal. Byinserting the SIM card into another GSM or 3G terminal, the user is ableto receive calls, make calls and receive other subscribed services fromthat terminal.

FIG. 1 shows a conventional 3G UMTS 100 which includes a typical MS orUE 105 having a handset 110 with a respective USIM or SIM card 115inserted therein. The USIM or SIM card 115 stores Public Land MobileNetwork (PLMN) information and IMSI information. When a request toconnect the MS 110 is received (by dialing or receiving a call) (S1),the PLMN and IMSI information is transferred from the USIM or SIM card115 to the handset 110 for facilitating an initial cell search and tocamp on the cell determined from the search (S2). A communication linkbetween the MS or UE 105 and a UTRAN node 120 is established, and systeminformation is sent from the UTRAN node 120 to the MS or UE 105 (S3A,S3B). In response, the MS or UE 105 sends a connection request includingthe stored IMSI information to the UTRAN node 120 (S4). Once theconnection is granted by the UTRAN node 120 (S5A, S5B), the MS or UE 105may be used to request a transfer and/or connection to a CS or PS Corenetwork 125 (S6A, S6B). Once the MS or UE 105 is connected to the Corenetwork 125 (S6B), data may be transferred between the Core network andthe MS or UE 105 (S7).

Protocol enhancements, specified by 3GPP TS 23.003, allow transparentrouting of IP datagrams to mobile nodes in the Internet. An IP datagramis the fundamental unit of information passed across any networkutilizing the Internet protocol. An IP datagram contains source anddestination addresses, along with data and a number of fields thatdefine such things as the length of the datagram, the header checksumand flags that indicate whether the datagram can be (or has been)fragmented.

Each mobile node is always identified by its home address, regardless ofits current point of attachment to the Internet. A mobile node is a hostor router that changes its point of attachment from one network orsub-network to another. A mobile node may change its location withoutchanging its IP address. Thus, a mobile node may continue to communicatewith other Internet nodes at any location using its constant IP address,assuming link-layer connectivity to a point of attachment is available.

When located away from its home, a mobile node is also associated with acare-of address, which provides information about its current point ofattachment to the Internet. The care-of address is the termination pointof a tunnel toward a mobile node. A tunnel is the path followed by adatagram while it is encapsulated. A foreign agent care-of message is anaddress of a foreign agent with which the mobile node is registered. Aco-located care-of message is an externally obtained local address whichthe mobile node has associated with one of its own network interfaces.

The protocol provides for registering the care-of address with a homeagent. A home agent is a router on a mobile node's home network whichtunnels datagrams for delivery to the mobile node when it is away fromhome, and maintains current location information for the mobile node.The home agent sends datagrams destined for the mobile node through atunnel to the care-of address. After arriving at the end of the tunnel,each datagram is then delivered to the mobile node.

In Internet routing, a care-of address is a temporary IP address for amobile node (mobile device) that enables message delivery when thedevice is connecting from somewhere other than its home network. Thecare-of address identifies a mobile node's current point of attachmentto the Internet and makes it possible to connect from a differentlocation without changing the device's home address (permanent IPaddress). This works similarly to the way the postal system mightforward letters through a care-of address: messages sent to the knownpermanent address are rerouted to the care-of address while therecipient can be reached there. Thus, the recipient avoids having tochange their official address to the temporary one when they changetheir location, and change it back again when they return home.

When a mobile device is away from its home network, it is assigned acare-of address. This may be a foreign agent care-of address, which isthe static IP address of a foreign agent on a visited network, or aco-located care-of address, which is a temporary IP address assigned tothe mobile node. A co-located care-of address may be acquired throughsome means such as Dynamic Host Configuration Protocol (DHCP), or may bea longer-term address assigned a device for connecting through aspecific foreign network. Mobile IP, as defined in the InternetEngineering Task Force (IETF) RFC 2002 specifications, registers thecare-of address with a home agent which resides on the home network.When a message for the mobile node is delivered to the home network, thehome agent intercepts the message and tunnels it to the recipient at thecare-of address.

UEs can only be operated if a valid IMSI is present. An IMSI isprimarily intended for obtaining PLMN information by subscribers forindividual charging purposes. Current cellular systems, however, do notaddress the use of an MS or UE in the context of an IP-based network. Asthe use of IP-based networks becomes ubiquitous, the lack of IP-enabledfunctionality will present a problem for many MS or UE users.

SUMMARY

As cellular systems move towards incorporating the features of anIP-based network, it is important to improve the functionality of an MSor UE (hereinafter “mobile unit”) with an IP address. The presentinvention identifies the mobile unit by an IP address stored in a SIM,USIM or any smart card that is being used in the mobile unit. Examplesof the type of IP addresses covered are IPv4, IPv6 and care of addressesused in Mobile IP.

In a preferred embodiment, the mobile unit includes a handset and aremovable storage module (e.g., SIM, USIM). The handset has a uniquehandset identity for transmitting, receiving and processing wirelesscommunications. The removable storage module has a unique storage moduleidentity for storing information specific to a user, including an IPaddress. Furthermore, the removable storage module may store PLMNinformation, IMSI information and User information. The handsetselectively transmits such information to one or more networks forestablishing a communications link with the networks.

The removable storage unit of the mobile unit may use the IMSIinformation and the IP address to access both an IP-based network and acellular network at the same time, thus allowing a user of the mobile toaccess the cellular network for carrying out voice communications whilequerying an IP-based network for data.

Alternatively, the mobile unit may drop an established connection withone first network and route existing services associated with the firstnetwork through a second network.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a conventional 3G UMTS which includes a typical MS or UE.

FIG. 2 shows a mobile unit including a handset and a removable storagemodule configured in accordance with a preferred embodiment of thepresent invention.

FIG. 3 illustrates the types of information stored in the removablestorage module of FIG. 2.

FIG. 4 is a system diagram illustrating how the mobile unit of FIG. 2communicates with a cellular network and an IP-based network inaccordance with one embodiment of the present invention.

FIG. 5 is a system diagram illustrating how the mobile unit of FIG. 2communicates with an All IP network in accordance with one embodiment ofthe present invention.

FIG. 6 is a system diagram illustrating how the mobile unit of FIG. 2communicates with a UTRAN node and Core network/IP network in accordancewith one embodiment of the present invention.

FIG. 7 is a system diagram illustrating how the mobile unit of FIG. 2communicates with a UTRAN node, Circuit Switched network and All IPnetwork in accordance with one embodiment of the present invention.

FIG. 8 is a flow chart illustrating the method steps for establishingcommunications between the mobile unit of FIG. 2 and a plurality ofnetworks whereby existing services associated with one network arerouted through another network in accordance with one embodiment of thepresent invention.

FIG. 9 is a flow chart illustrating the method steps for establishingsimultaneous communications between the mobile unit of FIG. 2 and aplurality of networks in accordance with one embodiment of the presentinvention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 2 shows a mobile unit 200 that is assigned an IP address whichpermits the mobile unit 200 to operate if the IP address is valid. TheIMSI and the IP address can coexist in the mobile unit 200, which can beidentified by either an IMSI, an IP address or both.

The mobile unit 200 includes a handset 205 having a unique handsetidentity for transmitting, receiving and processing wirelesscommunications. The mobile unit 200 further includes a removable storagemodule 210, having a unique storage module identity, which storesinformation specific to a user.

Referring to FIG. 3, the stored information in the removable storagemodule 210 includes an IP address 340. The IP address 340 is used togain access to an IP-based network for facilitating the transfer of datato and from the IP-based network. The stored information furtherincludes PLMN information 320, IMSI information 330 and User information350. The removable storage module 210 may be a Subscriber IdentityModule (SIM), a Universal Mobile Telecommunication System (UMTS)Subscriber Identity Module (USIM) or any other type of smart card.

FIG. 4 shows a system 400 including at least one mobile unit 200, acellular network 405 and an IP-based network 410. The mobile unit 200selectively transmits an IP address 340 and IMSI information 330, storedin the removable storage module 210 (shown in FIG. 2) of the mobile unit200, to one or more networks, such as a cellular network 405 and anIP-based network 410. The mobile unit 200 has multi-network capabilitiesallowing it to communicate with the IP-based network 410 and thecellular network 405 at the same time. The mobile unit 200 communicateswith the cellular network 405, via a connection established using theIMSI information 330 (S8, S9), to transmit and receive cellular services(S10). The mobile unit 200 communicates with the IP-based network 410(S11, S12) using the IP address to transmit and receive IP data services(S13). In one embodiment, the connection established with the cellularnetwork 405 may be dropped and the existing cellular network servicesmay be provided through the IP-based network 410. In another embodiment,mobile unit 200 may simultaneously communicate with the cellular network405 and the IP-based network 410. Alternatively, mobile unit 200 maycommunicate with a wireless local area network (LAN), rather thanIP-based network 410.

FIG. 5 shows a system 500 including at least one mobile unit 200 and anAll IP network 505 capable of exchanging messages with the mobile unit200. The mobile unit 200 has stored therein an IP address which allowsthe mobile unit to connect to the All IP network 505 without goingthrough a cellular network, provided the mobile unit is able to accessthe IP network at the physical layer. When a request to connect themobile unit 200 is received (by dialing or receiving a call) (S14), thePLMN information 320, IP address 340 and User information 350 aretransferred from the removable storage module 210 to the handset 205 forfacilitating an initial cell search and to camp on the cell determinedfrom the search (S15). A communication link between the mobile unit 200and the All IP network 505 is established, and system information issent from the All IP network 505 to the mobile unit 200 (S16A, S16B). Inresponse, the mobile unit 200 sends a connection request including thestored IP address 340 and User information 350 to the All IP network 505(S17). Once the connection is granted by the All IP network 505 (S18A,S18B), the transfer of data between the mobile unit 200 and the All IPnetwork 505 may commence (S19).

FIG. 6 shows a system 600 including at least one mobile unit 200, aUTRAN node 605 and a Core network/IP network 610. When a request toconnect the mobile unit 200 is received (by dialing or receiving a call)(S20), the PLMN information 320, IMSI information 330 and IP address 340are transferred from the removable storage module 210 to the handset 205for facilitating an initial cell search and to camp on the celldetermined from the search (S21). A communication link between themobile unit 200 and the UTRAN node 605 is established, and systeminformation is sent from the UTRAN node 605 to the mobile unit 200(S22A, S22B). In response, the mobile unit 200 sends a connectionrequest including the stored IMSI information 330 to the UTRAN node 605(S23). Once the connection is granted by the UTRAN node 605 (S24A,S24B), the mobile unit 200 may be used to request a transfer and/orconnection to the CS or PS Core network/IP network 610 (S25A, S25B),whereby the UTRAN node 605 forwards the IP address 340 to the Corenetwork/IP network 610 (S25B). Once the mobile unit 200 is connected tothe Core network/IP network 610, data may be transferred between theCore network/IP network 610 and the mobile unit 200 (S26).

FIG. 7 shows a system 700 including at least one mobile unit 200, aUTRAN node 705, a Circuit Switched network 710 and an All IP network715. When a request to connect the mobile unit 200 is received (bydialing or receiving a call) (S27), the PLMN information 320, IMSIinformation 330, IP address 340 and User information 350 are transferredfrom the removable storage module 210 to the handset 205 forfacilitating an initial cell search and to camp on the cell determinedfrom the search (S28). A communication link between the mobile unit 200and the UTRAN node 705 is established, and system information is sentfrom the UTRAN node 705 to the mobile unit 200 (S29A, S29B). Inresponse, the mobile unit 200 sends a connection request including thestored IMSI information 330 to the UTRAN node 705 (S30). Once theconnection is granted by the UTRAN node 705 (S31A, S31B), the mobileunit 200 may be used to request a transfer and/or connection to theCircuit Switched network 710 (S32A, S32B). Once the mobile unit 200 isconnected to the Circuit Switched network 710, data may be transferredbetween the Circuit Switched network 710 and the mobile unit 200 (S33).The mobile unit 200 also sends a connection request including the storedIP address 340 and User information 350 to the All IP network 715 (S34).Once the connection is granted by the All IP network 715 (S35A, S35B),the transfer of data between the mobile unit 200 and the All IP network505 may commence independent of other connections to circuit switcheddata (S36).

FIG. 8 is a flow chart illustrating method steps for implementing oneembodiment of the present invention, whereby communications areestablished between a mobile unit 200 and a plurality of networks. Themobile unit 200 includes a removable storage module 210 having a uniquestorage module identity, as described herein. In step 805, informationspecific to a user is provided in the removable storage module 210. Theinformation includes an IP address. In step 810, the mobile unit 200communicates with a first one of said networks via an establishedconnection. In step 815, the mobile unit 200 accesses a second one ofthe networks using the IP address. In step 820, the mobile unit 200drops the established connection with the first network and routesexisting services associated with the first network through the secondnetwork. The first network may be a cellular network and the secondnetwork may be an IP network.

FIG. 9 is a flow chart illustrating method steps for implementinganother embodiment of the present invention, whereby communications areestablished between a mobile unit 200 and a plurality of networks. Themobile unit 200 includes a removable storage module 210 having a uniquestorage module identity, as described herein. In step 905, informationspecific to a user is provided in the removable storage module 210. Theinformation includes an IP address. In step 910, the mobile unit 200communicates with a first one of said networks via an establishedconnection. In step 915, the mobile unit 200 accesses a second one ofthe networks using the IP address. In step 920, the mobile unit 200simultaneously communicates with the first and second networks. As shownin FIG. 9, the first network may be a cellular network and the secondnetwork may be an IP network.

The present invention has several key benefits over prior art systems.First, the IP address stored in the mobile unit 200 can be used inscenarios for handoff between a cellular system and a Wireless LAN(Local Area Network). Second, if the mobile unit 200 has an IP addresswith which it can be identified, then it is possible to connect to anIP-based network, such as the Internet, without going through a cellularnetwork.

While the present invention has been described in terms of the preferredembodiment, other variations which are within the scope of the inventionas outlined in the claims below will be apparent to those skilled in theart.

1. In a mobile unit, a method for communicating between the mobile unitand a plurality of networks, the method comprising: storing in aremovable storage medium a plurality of user-specific informationelements such that each information element is usable for establishing aconnection with a different type of network; and establishing a firstconnection with a first network using a first information element; andestablishing a second connection with a second network using a secondinformation element.
 2. The method of claim 1 wherein the firstconnection is established using an internet protocol (IP) network and anIP address.
 3. The method of claim 2 wherein the first connection isestablished with a wireless local area network (WLAN).
 4. The method ofclaim 3 wherein the second connection is established with a cellularnetwork which is connected using an international mobile subscriberidentity (IMSI).
 5. The method of claim 1 further comprising droppingthe first connection after the second connection is established.
 6. Themethod of claim 5 wherein the mobile unit continues to receive a serviceinitially received via the first connection via the second connectionafter the first connection is dropped.
 7. The method of claim 1 whereinthe second connection is established through the first connection.
 8. Amobile unit for use in conjunction with multiple communication networkscomprising: a removable storage module configured to store a pluralityof user-specific information elements, wherein each information elementis usable for establishing a connection with a different type ofnetwork; and a processor configured to establish a first connection witha first network using a first information element stored in the storagemodule, and a second connection with a second network using a secondinformation element stored in the storage module.
 9. The mobile unit ofclaim 8 wherein the removable storage module is configured to store aninternet protocol (IP) address of the mobile unit.
 10. The mobile unitof claim 9 wherein the removable storage module is configured to storean international mobile subscriber identity (IMSI) information.
 11. Themobile unit of claim 8 wherein the removable storage module isconfigured as one of a subscriber identity module (SIM), a universalmobile telecommunication system (UMTS) subscriber identity module(USIM), or a smart card.
 12. The mobile unit of claim 8 wherein theprocessor is configured to establish one connection with an IP networkusing an IP address, and another connection with a cellular networkusing an international mobile subscriber identity (IMSI).
 13. The mobileunit of claim 8, wherein the processor is configured to drop the firstconnection after the second connection is established.
 14. The mobileunit of claim 13 wherein the processor is configured to continue toreceive service initially received via a second connection after a firstconnection is dropped.
 15. The mobile unit of claim 8 wherein theprocessor is configured to establish the second connection through thefirst connection.